Flood Warning Issued for La Salle County, Illinois
This alert is no longer in effect.
NOAA issued it on April 26, 2026, 3 months ago. Warnings of this kind stay in effect for hours to a few days, so this page is a historical record of what was issued, not a current warning. For conditions where you are right now, check weather.gov (US), weather.gc.ca (Canada), the Met Office (UK), or the Bureau of Meteorology (Australia).
Areazine synthesizes this NWS weather alert directly from NOAA's official public data feed. See our methodology for full source attribution and refresh cadence.
The National Weather Service has issued a Flood Warning for La Salle County, Illinois, due to expected minor flooding on the Illinois River starting this afternoon and lasting until early Tuesday.
Read this weather record in 30 seconds
- Record type
- Flood Warning
- Affected area
- La Salle County, Illinois
- Issued
- April 26, 2026
- Issuing authority
- NWS Chicago IL
Flood notices turn on location and timing. Treat the named area as this record's scope; do not assume nearby counties, parishes, or waterways were included.
Record status: historical. It was issued 3 months ago; use the issuing agency's live warning service for current conditions in La Salle County, Illinois.
Alert Details
A Flood Warning has been issued by the National Weather Service (NWS) Chicago IL. This alert is for the event code FLW and is classified as severe.
Affected Areas
The warning affects La Salle County, Illinois, specifically the Illinois River from Heritage Harbor east of Ottawa downstream to Starved Rock Lock and Dam, including the Ottawa gauge.
What You Should Do
Persons along rivers and streams in the warned area should take immediate precautions to protect life and property. These forecasts are based on observed and forecast precipitation.
Expected Conditions
Minor flooding is forecast. At 462.5 feet, the roadway entrance to Allen Park in Ottawa is threatened, and the Allen Park west boat ramp is inundated. At 464.0 feet, backwater causes the Fox River to reach bankfull near St. Elizabeth Medical Center in Ottawa. The current stage is 462.2 feet, and the river is expected to rise above the flood stage of 463.0 feet later today.
Timeline
The warning is effective from April 18, 2026, at 5:44 AM CDT, with onset at 1:00 PM CDT on April 18, 2026. It expires at 11:45 PM CDT on April 18, 2026, and ends at 1:00 PM CDT on April 21, 2026.
Original source: NOAA Official Notice ↗
Related Weather Alerts
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Two Areazine-derived peer sets for this NWS weather alert: nearest notices by body length and by same severity near the same agency date. Peers come from other categories so they are not the same-feed Related list above.
Similar body length
Nearest notices by article body length (1,181 characters here).
Similar severity timing
Same severity (high) notices issued closest in time to April 26, 2026.
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